| Summary: | 碩士 === 國立臺灣科技大學 === 化學工程系 === 103 === The heterogeneous kinetics behavior was investigated with a batch reactor for the synthesis of ethyl ferulate from ferulic acid with ethanol over cation-exchange resins, Amberlyst 39. The experiments wereconducted at temperatures from 323.15 K to 343.15 K. Additionally, the effects of molar ratio of ethanol to acid in the feed stream, the mass transfer resistance on the catalytic reaction, and the different levels of catalyst loadings were also observed.
The reaction rateof acid increased with increase of reaction temperature, molar ratio ofethanol to acidin the feed stream, catalyst loading, and agitation speed. Furthermore, the equilibrium conversion of acid increased with increase of reaction temperature and molar ratio of ethanol to acid in the feed stream.The relative adsorption strengths of the reacting species were determined by adsorption experiments.The resultsindicated that the magnitude of adsorption strengths on Amberlyst 39 followed the order of water >ethanol>ethyl ferulate.
The kinetic data of the synthesis of ethyl ferulate were correlated with theideal-quasi-homogeneous (IQH),the non-ideal-quasi-homogeneous(NIQH), theEley-Rideal(ER),the Langmuir-Hinshelwood-Hougen-Watson (LHHW) and theLangmuir-Hinshelwood-Hougen-Watson with Ka (LHHW-Ka) models,respectively. The optimal values of the kinetic parameters were determined from the data fitting. The NRTL model was used to calculate the activity coefficients for each reacting species. The LHHWmodel yielded the best representation for the kinetic behavior of heterogeneous catalytic synthesis ofethyl ferulate.
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